Military tanks and artillery that Qatar imported from Germany are on their way to the Gulf state but a controversy over the sale had the European powerhouse defending its decision to supply.

Bonn said it was confident the arms would not be used in a war in Yemen between government supporters and the Iran-allied Houthis, according to a Reuters report.

The newspaper Sueddeutsche Zeitung reported that four German Leopard 2 tanks and three howitzers had recently been shipped from Germany, bound for Qatar. The shipment is controversial because German Economy Minister Sigmar Gabriel vowed last year to be much more cautious in licensing arms exports, and because Berlin is seeking to de-escalate tensions in the Middle East.

“Regarding Yemen, Qatar explicitly has no plans for the delivery of combat equipment and is supporting the situation there by delivering humanitarian aid supplies,” German government spokeswoman Christiane Wirtz said.

“We are rather confident that those weapons can and will not be deployed in current armed conflicts, such as in Yemen,” Foreign Ministry spokesman Martin Schaefer said.

However, military sources told Reuters in September that Qatari troops were headed to Yemen and preparing to join a new push against Houthi positions in the country›s capital, Sanaa.

Wirtz said the export of the arms was approved in 2013 under the previous government but that the deal still had the support of Chancellor Angela Merkel’s office.

“In the view of the chancellery, such a delivery is justifiable,” Wirtz told a regular government news conference.

The 2013 agreement allowed Munich-based arms manufacturer Krauss-Maffei Wegmann to export a total of 62 Leopard 2 tanks and 24 howitzers, worth 2 billion euros ($2.21 billion), the Sueddeutsche said. The recent shipment was the first of those exports.

Gabriel’s promise last year on licensing arms exports unnerved Germany›s sizeable defence industry and signalled a change in policy from the previous coalition government, under which sales rose.

Gabriel’s Social Democrats (SPD) were not part of that government, in which Merkel’s conservatives ruled in coalition with the Free Democrats. The SPD is now junior coalition partner with Merkel’s conservatives.

A spokeswoman for Gabriel’s Economy Ministry said checks had been made on the permission granted to deliver the arms to Qatar and the conclusion was that it could not be revoked.

“The minister ... has made clear that he considers tank deliveries to the Arabic region to be problematic,” the spokeswoman added.

Despite Gabriel’s pledge, Berlin approved significantly more arms exports in the first half of this year, official figures showed.

Gulf Industry, published by Al Hilal Group has now established itself as a "must-read" publication for anyone with an involvement in the region's industrial sector whether as manufacturers, distributors or related service organisations.The publication represents a "window" into the Gulf's manufacturing trading and export sectors providing news, views analysis and information across virtually every industry related sector.